Movable partitions, such as folding doors are often implemented in various settings, such as in hotels, convention centers, schools, churches and other buildings, to subdivide a single large room into two or more smaller rooms. For example, referring to FIG. 1, a prior art version of an accordion-style folding partition 100 is shown. The folding partition 100 includes two panels 102A and 102B connected, at longitudinal ends thereof; to a lead post 104. Each panel 102A and 102B includes a plurality of panel sections 106, which are hingedly connected together with hinges 108, or similar folding or hinge-like structures. The hinged connection of the panel sections 106 allows the partition 100 to be compactly stored in a plicated or accordion manner when in a compacted or folded state. When the partition is required to be opened or closed, the partition 100 may be motivated along a track 110 by an electric motor or other drive mechanism, or manually by a user pulling or pushing the partition 100 along the track 110.
Between the two panels 102A and 102B is a space that may be termed an air space 112 and which may work together with the panels 102A and 102B to provide a sound barrier. Such a sound barrier is often desired when two areas or rooms, having been subdivided by the folding partition 100, are used at the same time for different classes, meetings or other functions to eliminate or reduce the amount of noise that may enter one room from an adjacent room.
The air space 112 between the two panels 102A and 102B is conventionally maintained as a relatively static environment. In other words, while not being completely sealed relative to the environment being subdivided by the partition 100, the partition 100 is constructed to substantially limit air movement from one side of the partition 100 to the other side of the partition 100 when in a deployed or extended state. The limitation of airflow across the partition 100 is beneficial from a sound insulation standpoint as it also limits the path of potential sound waves across a deployed partition 100.
Thus, while the existence of an air space 112 is beneficial in a number of ways, the construction of the partition 100 to limit airflow when the partition 100 is deployed presents some difficulties when extending or retracting the partition 100. For example, when the partition 100 is being retracted for storage, a substantial amount of air contained in the air space 112 needs to be discharged in order to enable the partition 100 to fold or collapse. Likewise, air needs to be drawn into the air space 112 when the partition 100 is extended to a closed position. In other words, the air space 112 or the volume between the two panels 102A and 102B increases when the partition 100 is deployed and decreases when the partition 100 is retracted.
If the partition 100 is substantially sealed relative to the air space 112, the air contained in the air space 112 is unable to easily escape from between the partition panels 102A and 102B (or be drawn therein) during operation. Thus, as the partition is being retracted, the air in the air space 112 compresses and acts as an air cushion, providing resistance to the retraction of the partition 100. Additionally, in seeking an outlet, the air within the air space 112 may cause the panels 102A and 102B (and particularly the bottom 114 of each panel 102A and 102B in most conventional partitions 100) to billow out away from one another, making it more difficult to operate the partition 100 and store the partition 100 in an associated pocket.
In an attempt to release air from between the panels 102A and 102B during operation of the partition 100, some partitions 100 have included openings or holes in the lead post 104 of the partition 100. However, such a configuration does not always provide sufficient air release depending, for example, on the size of the partition 100, the spacing of the panels 102A and 102B, and the speed at which the partition 100 is closed. Additionally, in some embodiments, an operator may displace the door by pushing or pulling the lead post 104 (or some other structure such as a handle located adjacent the lead post 104). In such a situation, there is the possibility of blowing debris into the operator's face. Furthermore, if openings are formed along both sides of the lead post 104, the ability of the partition 100 to act as a sound barrier or a fire barrier may be substantially compromised.
Some attempts have been made to provide an air release structure that releases air from the air space 112 through a location other than the lead post 104 while channeling air away from the user and without providing a path for sound to easily pass from one side of the extended partition 100 to the other. For example, in U.S. Pat. No. 3,447,584 to Smart, an air release construction for a folding door is provided comprising an overhead track unit incorporating an air-release chamber therein. Air passages are provided between the door chamber or air space and an overhead track air-release chamber so as to allow air to move between the two chambers. Thus, air flows to or from the air space, through the air-release chamber, and out to the environment surrounding the door during the closing or extension thereof. Air flows in a reversed path during the opening or the retraction of the door.
While the configuration described by Smart appears to provide some airflow from a chamber or air space between panels and an exterior location, such a configuration appears to be somewhat limited in that, when initially opening the door to place it back in a stored condition, a substantial amount of air may enter into the overhead track air-release chamber but only a limited amount of air may be released therefrom due to the limited number of air passages in the overhead chamber that are exposed to an external environment. In other words, the number of passages that are exposed to the external environment when the door is in such a condition is substantially limited, but the number of passages exposed to the door chamber or air space are relatively numerous. Additionally, the converse is true when initially displacing the door to position it in an extended or closed position.